Pain in the lower abdomen is usually related to gastrointestinal diseases or female reproductive conditions.
Lower abdominal pain may be dull or sharp, intermittent or constant, mild or severe. Pain may also radiate to other parts of the abdomen, or parts of the body such as the back, flank, or shoulder.
Symptoms of lower abdominal pain depend on the cause.
Symptoms that may accompany lower abdominal pain may include:
- Nausea
- Vomiting (may include vomiting blood)
- Fever
- Chills
- Sweating
- Fatigue
- Feeling unwell (malaise)
- Light-colored stools
- Abdominal distention/bloating
- Lower extremity swelling (edema)
- Gastrointestinal bleeding
- Weight loss
- Abdominal tenderness
- Dark urine
- Blood in urine
- Urinary frequency or urgency
- Difficulty urinating
- Pain on urination
- High-pitched or absent bowel sounds
- Gas (flatulence)
- Altered mental status
- Low blood pressure (hypotension)
- Bulky, foul-smelling, floating stools
- Altered bowel habits
- Pelvic pain
If you experience any of the following symptoms with lower abdominal pain, see a doctor because these may be a sign of a more serious condition:
- Pain is severe and lasts more than an hour or comes and goes for more than 24 hours
- Pain starts suddenly
- Fever greater than 102°f (39°c)
- Black, tarry stool
- Bloody bowel movements
- Vomiting
- Inability to eat or drink for several hours
- Diarrhea
- Weight loss without trying
- Loss of appetite
- Feeling a lump in the abdomen
What Causes Lower Abdominal Pain?
There are many possible causes of lower abdominal pain.
Causes of lower abdominal pain that are localized to one side include:
- Acute appendicitis
- Kidney stones
- Diverticulitis
- Pyelonephritis
Causes of lower abdominal pain that may not always be localized to one side include:
- Acute urinary retention
- Cystitis
- Infectious colitis
Causes of lower abdominal pain that are considered diffuse, meaning they have nonspecific or variable patterns of pain include:
- Inflammatory bowel disease (IBD): ulcerative colitis and Crohn disease
- Celiac Disease
- Intestinal obstruction
- Food poisoning
- Irritable bowel syndrome (IBS)
- Constipation
- Lactose intolerance
- Diverticulosis
- Perforation of gastrointestinal tract
- Mesenteric ischemia
- Viral gastroenteritis
- Spontaneous bacterial peritonitis
- Peritonitis in peritoneal dialysis patients
- Cancer
- Ketoacidosis
- Adrenal insufficiency
Causes of lower abdominal pain in women include:
- Pregnancy/pregnancy complications
- Ectopic pregnancy
- Pelvic inflammatory disease
- Fibroids (leiomyomas)
- Endometriosis
- Endometritis
- Ovarian torsion
- Ruptured ovarian cyst
- Ovarian hyperstimulation
- Ovarian cancer
Causes of lower abdominal pain in postoperative patients include:
- Postoperative ileus
- Surgical site infections
- Hematoma/seroma formation and nerve injury
How Is Lower Abdominal Pain Diagnosed?
The diagnosis of the cause of lower abdominal pain begins with a history and physical exam. Depending on the patient’s symptoms and the specific location of the lower abdominal pain, the physical exam may involve a rectal examination and/or a pelvic examination.
Blood tests to help diagnose the cause of lower abdominal pain include:
- Complete blood count (CBC) with differential
- Electrolytes, blood urea nitrogen (BUN), creatinine, and glucose
- Aminotransferases, alkaline phosphatase, and bilirubin
- Calcium
- Lipase and/or amylase
- Serum iron, total iron binding capacity, and ferritin
- Anti-tissue transglutaminase
- Pregnancy testing for women
Imaging tests to help diagnose the cause of lower abdominal pain include:
- Ultrasound
- Computed tomography (CT) scan
- Magnetic resonance imaging (MRI; including magnetic resonance cholangiopancreatography)
- Endoscopy
- Endoscopic retrograde cholangiopancreatography
Other tests to help diagnose the cause of lower abdominal pain may include:
From 
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